DOCSLIB.ORG

Dynamics of Exozodiacal Clouds

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Dynamics of Exozodiacal Clouds Dynamics of Exozodiacal Clouds Marc Kuchner, Christopher Stark, NASA GSFC Olivier Absil and Jean-Charles Augereau, Grenoble Observatory and Philippe Thébault, Paris Observatory The inner Solar System contains a cloud of small (1-100 µm) dust grains created when small bodies---asteroids, comets, and Kuiper belt objects---collide and outgas. This dust cloud, the zodiacal cloud probably has extrasolar analogs, exozodiacal clouds. Exozodiacal clouds are related to debris disks, clouds of rocks and dust orbiting main sequence stars thought to represent the debris left over from planet formation. Some debris disks appear to contain distinct inner clouds that could be considered massive exozodiacal clouds (e.g. Koerner et al. 1998, Absil et al. 2006). This white paper addresses the need for future theoretical work on the dynamics of exozodiacal clouds. This theoretical work should help us discover new planets and understand exozodiacal clouds as astrophysical noise. So far, observations of nearby stars have not provided good constraints on the structures of exozodiacal clouds. But future observations probably will demand a better theoretical understanding of these systems. Recognizing Planets Via Disk Structures: As zodiacal dust particles spiral inwards under the effect of Poynting-Robertson drag, they interact dynamically with the planets, and sometimes become temporarily trapped in mean motion resonances (MMRs) with planets. This resonant trapping can produce a detectable density structure in the dust cloud. The solar zodiacal cloud shows evidence of this kind of pattern and other structures created by planet – dust interactions. It also bears the signatures of individual comets and individual collisional cascades in the asteroid belt. Figure 1: Ring of dust trapped in mean motion Figure 1 shows a surface density resonances with a 5 Earth-mass planet (Stark & map for a simulated dust cloud Kuchner 2007, in preparation). containing a 5 Earth-mass planet computed using the Thunderhead supercomputer at Goddard (Stark & Kuchner 2007, in preparation). The map shows a torus of dust trapped in MMRs with the planet. Recognizing these structures in images of exozodiacal clouds and debris disks can allow us to indirectly detect extrasolar planets that otherwise would go unseen and measure their masses and orbital parameters. This method may be the only way to detect extrasolar planets in long orbital periods (e.g. ~100 years) that are not self-luminous. Recognizing planets this way in massive debris disks (like the disk around β Pictoris) can be fraught with degeneracies and modeling uncertainties. However, upcoming telescopes like LBTI (the Large Binocular Telescope Interferometer), Figure 2: Simulated image of a Solar System ALMA, JWST and many proposed analog (minus Venus) as seen by baseline missions like TPF, Eclipse, EPIC, TPF-C at 10 pc. Most of the signal is FKSI, SPIRIT, etc. have the potential exozodiacal light. (Kuchner) to find debris disks with much less optical depth than the ones known now. These sparse disks should have physics that is relatively simple and similar to that of the solar zodiacal cloud, allowing us to decode their structures straightforwardly, if our theoretical progress has prepared us. Dust Patterns as Astrophysical Noise: Exozodical dust is important as a potential source of astrophysical noise for planet finding; this concern also drives modeling efforts. The capability of imaging extrasolar planets carries with it the capability of imaging exozodiacal clouds. For example, the solar zodiacal cloud is the brightest component of the solar system in the optical and infrared except for the Sun. In a sense, TPF might be appropriately called the Exozodiacal Cloud Finder. Figure 1 shows a view of how the solar system (minus Venus) would appear to the current baseline TPF-C (Terrestrial Planet Finder-Coronagraph) design. Most of the light in the image comes from exozodiacal dust. The Earth appears as a difference between the shapes of the two lobes of the image. As Figure 1 suggests, ~10% surface brightness fluctuations in a bright exozodiacal cloud on the scale of ~0.1 AU can masquerade as terrestrial planets to TPF; they become confusion noise. Photon noise in the light from exozodiacal clouds limits the spectroscopic capability of planet-imaging telescopes like TPF. We need better tmodels to predict the power level in these noise terms. Work Needed Quantitative Models of Surface Brightness and Contrast: Models of steady state zodiacal cloud dynamics have come a long way since Dermott et al (1994) first recognized the leading/trailinig asymmetry in the surface brightness of the infrared sky as a circumsolar ring of zodiacal dust trapped in MMRs with the Earth. We now more-or-less understand the geometry of resonant signatures from analytical calculations (Kuchner & Holman 2002) and numerical simulations (e.g. Deller & Maddison 2005). Figure 3 shows some of the basic density wave patterns associated with various MMRs (Kuchner & Holman 2002). However, although the geometry of the resonances has become reasonably well understood, the way resonances are 3:2 populated is hard to model. In a way, modeling exozodiacal clouds is like modeling the spectra of stars; it’s easy to understand where the lines (the resonances) are, but it’s harder to model how strong the lines (how populated the resonances) are. This uncertainty limits our ability to model 2:1 the surface brightness perturbations created by planets in dust clouds. Figure 3 shows the results of a simulation by Moro-Martin and Malhotra (2003) showing the semi-major axis distribution of dust interacting with a Neptune-like planet. 3:1 The three curves show the results of three simulations of 100 particles each. The differences between the curves show that the three simulations populated the MMRs differently, resulting in three Figure 3: Density wave patterns associated different model images. This Figure with some of the key MMRs. The stars are suggests that future simulations will need the stars; the filled circles are the planets. thousands of particles in each size bin to Patterns associated with low-eccentricity reduce this Poisson noise to the level planets are on the left; patterns for high- where they can produce reliable eccentricity planets are on the right. (Kuchner & Holman 2002) quantitative predictions of the contrast in any resonant structure. This computational power is within easy reach of today’s large computer clusters. Multiple-Planet Systems Many extrasolar planet systems contain multiple planets. So far, the only multiple-planet system that has been examined in detail—including planet-planet interactions---is the Solar System. Multiple planets present a special numerical challenge because they add another time scale to the problem: the time scale of secular orbital evolution. Handling the secular dynamical effects will requires more algorithm development and more computational power. Figure 4: Semi-major axis distribution for 3 simulations of resonant trapping. The different simulations show different populations of the major resonances (Moro - Martin & Malhotra 2003). Collisional Effects and Gas Drag For exozodiacal clouds with optical depths >50 times that of the solar zodiacal cloud, grain-grain collisions become important. There have been some efforts to model what this phenomenon does to the three-dimensional distribution of dust in these clouds (e.g. Kehoe & Dermott 2005). However, the problem of modeling collisions in exozodiacal dust clouds is fundamentally challenging because the number of particles is large (1030) and the collisional cross-sections are small (10-32 AU2), and it has never been treated in a self-consistent manner. Understanding collisional effects is crucial to understanding the dynamics of most currently known debris disks, which have optical depths 100-10,000 times that of the solar zodiacal cloud. This problem may yield to a statistical treatment (see Thébault et al. 2003, Krivov et al. 2006). In these massive disks, gas drag can also become important. Recent spectroscopic measurements show that some debris disks contain dynamically-significant quantities of atomic and molecular gas, perhaps released during collisions (e.g. Roberge et al. 2006, Chen et al. 2006). Thebault & Augereau (2005) and others have modeled the consequences of gas drag on the one-dimensional structure of circumstellar clouds, but the three-dimensional effects have not yet been studied. Observational Tests Presently, there is only one known example of a dust cloud structure created by a planet where we know from independent observations what the mass and orbit of the planet are: the Earth’s circumsolar ring. This ring has been observed by IRAS and COBE and is now being observed by Spitzer. The geometry of this ring is somewhat well understood, but the contrast between this ring and the background clouds is not! We need to find and model more examples of this phenomenon and we need better observations of the solar system and other planetary systems to build confidence in the models. References Absil, O. et al. 2006, A&A, 452, 237, Circumstellar material in the Vega inner system revealed by CHARA/FLUOR Chen, C.H. 2006, in New Horizons in Astronomy: Frank N. Bash Symposium, ASP Conference Series, Vol. 352, Proceedings of the Conference Held 16-18 October, 2005 at The University of Texas, Austin, Texas, USA, p.63, Dust and Gas Debris around Main Sequence Stars Deller, A.T. & Maddison, S.T. 2005, ApJ, 625, 398, Numerical modelling of dusty debris disks. Dermott, S.F. et al. 1994, Nature 369, 719, A circumsolar ring of asteroidal dust in resonant lock with the Earth. Kehoe, T. & Dermott, S. 2005, in Dust in Planetary Systems, Proceedings of the conference held September 26-28, 2005 in Kaua'i, Hawaii, 1280, 88, The Effect of Inter-Particle Collisions on the Dynamical Evolution of Asteroidal Dust and the Structure of the Zodiacal Cloud Koerner, D.W., Ressler, M.E., Werner, M.W. & Backman, D.E. 1998, ApJ, 503, L83, Mid-Infrared Imaging of a Circumstellar Disk around HR 4796: Mapping the Debris of Planetary Formation Krivov, A.V., Lohne, T., Sremcevic, M.
Load more

Recommended publications
  • Astrophysics Division Astrophysics Douglas Hudgins Program Scientist, Exoplanet Exploration Program Key NASA/SMD Science Themes
    National Aeronautics and Space Administration NASA and the Search for Life on Planets around Other Stars A presentation to the National Academies Committee on Exoplanet Science Strategy 6 March 2018 Paul Hertz Director, Astrophysics Division Astrophysics Douglas Hudgins Program Scientist, Exoplanet Exploration Program Key NASA/SMD Science Themes Protect and Improve Life on Earth Search for Life Elsewhere Discover the Secrets of the Universe 2 Talk summary 3 NASA’s Exoplanet Exploration Program Space Missions and Mission Studies Public Communications Kepler, WFIRST Decadal Studies K2 Starshade Coronagraph Supporting Research & Technology Key Sustaining Research NASA Exoplanet Science Institute Technology Development Coronagraph Masks Large Binocular Keck Single Aperture Telescope Interferometer Imaging and RV High-Contrast Deployable Archives, Tools, Sagan Fellowships, Imaging Starshades Professional Engagement NN-EXPLORE https://exoplanets.nasa.gov 4 Foundational Documents for the NASA’s Astrophysics Division 5 NASA’s cross-divisional Search for Life Elsewhere ASTROPHYSICS • Exoplanet detection and Planetary SCIENCE/ characterization ASTROBIOLOGY • Stellar characterization • Comparative planetology • Mission data analysis • Planetary atmospheres Hubble, Spitzer, Kepler, • Assessment of observable TESS, JWST, WFIRST, biosignatures etc. • Habitability EARTH SCIENCES • GCM • Planets as systems PLANETARY SCIENCE RESEARCH HELIOPHYSICS • Exoplanet characterization • Stellar characterization • Protoplanetary disks • Stellar winds • Planet formation • Detection of planetary • Comparative planetology magnetospheres 6 Exoplanet Exploration at NASA 2007 - present 7 The Spitzer Space Telescope For the last decade, the Spitzer Space Telescope has used both spectroscopic and photometric measurements in the mid-IR to probe exoplanets and exoplanetary systems. • Spitzer follow up observations of known transiting systems have revealed additional, new planets and helped refine measurements of the size and orbital dynamics of known planets as small as the Earth.
    [Show full text]
  • Exep Science Plan Appendix (SPA) (This Document)
    ExEP Science Plan, Rev A JPL D: 1735632 Release Date: February 15, 2019 Page 1 of 61 Created By: David A. Breda Date Program TDEM System Engineer Exoplanet Exploration Program NASA/Jet Propulsion Laboratory California Institute of Technology Dr. Nick Siegler Date Program Chief Technologist Exoplanet Exploration Program NASA/Jet Propulsion Laboratory California Institute of Technology Concurred By: Dr. Gary Blackwood Date Program Manager Exoplanet Exploration Program NASA/Jet Propulsion Laboratory California Institute of Technology EXOPDr.LANET Douglas Hudgins E XPLORATION PROGRAMDate Program Scientist Exoplanet Exploration Program ScienceScience Plan Mission DirectorateAppendix NASA Headquarters Karl Stapelfeldt, Program Chief Scientist Eric Mamajek, Deputy Program Chief Scientist Exoplanet Exploration Program JPL CL#19-0790 JPL Document No: 1735632 ExEP Science Plan, Rev A JPL D: 1735632 Release Date: February 15, 2019 Page 2 of 61 Approved by: Dr. Gary Blackwood Date Program Manager, Exoplanet Exploration Program Office NASA/Jet Propulsion Laboratory Dr. Douglas Hudgins Date Program Scientist Exoplanet Exploration Program Science Mission Directorate NASA Headquarters Created by: Dr. Karl Stapelfeldt Chief Program Scientist Exoplanet Exploration Program Office NASA/Jet Propulsion Laboratory California Institute of Technology Dr. Eric Mamajek Deputy Program Chief Scientist Exoplanet Exploration Program Office NASA/Jet Propulsion Laboratory California Institute of Technology This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. © 2018 California Institute of Technology. Government sponsorship acknowledged. Exoplanet Exploration Program JPL CL#19-0790 ExEP Science Plan, Rev A JPL D: 1735632 Release Date: February 15, 2019 Page 3 of 61 Table of Contents 1.
    [Show full text]
  • Overview and Reassessment of Noise Budget of Starshade Exoplanet Imaging
    Overview and reassessment of noise budget of starshade exoplanet imaging a,b, a a a Renyu Hu , * Doug Lisman, Stuart Shaklan , Stefan Martin , a a Phil Willems , and Kendra Short aJet Propulsion Laboratory, California Institute of Technology, Pasadena, California, United States bCalifornia Institute of Technology, Division of Geological and Planetary Sciences, Pasadena, California, United States Abstract. High-contrast imaging enabled by a starshade in formation flight with a space telescope can provide a near-term pathway to search for and characterize temperate and small planets of nearby stars. NASA’s Starshade Technology Development Activity to TRL5 (S5) is rapidly maturing the required technologies to the point at which starshades could be integrated into potential future missions. We reappraise the noise budget of starshade-enabled exoplanet imaging to incorporate the experimentally demonstrated optical performance of the starshade and its optical edge. Our analyses of stray light sources—including the leakage through micro- — meteoroid damage and the reflection of bright celestial bodies indicate that sunlight scattered by the optical edge (i.e., the solar glint) is by far the dominant stray light. With telescope and observation parameters that approximately correspond to Starshade Rendezvous with Roman and Habitable Exoplanet Observatory (HabEx), we find that the dominating noise source is exo- zodiacal light for characterizing a temperate and Earth-sized planet around Sun-like and earlier stars and the solar glint for later-type stars. Further, reducing the brightness of solar glint by a factor of 10 with a coating would prevent it from becoming the dominant noise for both Roman −10 and HabEx.
    [Show full text]
  • Starshade Rendezvous Probe
    Starshade Rendezvous Probe Starshade Rendezvous Probe Study Report Imaging and Spectra of Exoplanets Orbiting our Nearest Sunlike Star Neighbors with a Starshade in the 2020s February 2019 TEAM MEMBERS Principal Investigators Sara Seager, Massachusetts Institute of Technology N. Jeremy Kasdin, Princeton University Co-Investigators Jeff Booth, NASA Jet Propulsion Laboratory Matt Greenhouse, NASA Goddard Space Flight Center Doug Lisman, NASA Jet Propulsion Laboratory Bruce Macintosh, Stanford University Stuart Shaklan, NASA Jet Propulsion Laboratory Melissa Vess, NASA Goddard Space Flight Center Steve Warwick, Northrop Grumman Corporation David Webb, NASA Jet Propulsion Laboratory Study Team Andrew Romero-Wolf, NASA Jet Propulsion Laboratory John Ziemer, NASA Jet Propulsion Laboratory Andrew Gray, NASA Jet Propulsion Laboratory Michael Hughes, NASA Jet Propulsion Laboratory Greg Agnes, NASA Jet Propulsion Laboratory Jon Arenberg, Northrop Grumman Corporation Samuel (Case) Bradford, NASA Jet Propulsion Laboratory Michael Fong, NASA Jet Propulsion Laboratory Jennifer Gregory, NASA Jet Propulsion Laboratory Steve Matousek, NASA Jet Propulsion Laboratory Jonathan Murphy, NASA Jet Propulsion Laboratory Jason Rhodes, NASA Jet Propulsion Laboratory Dan Scharf, NASA Jet Propulsion Laboratory Phil Willems, NASA Jet Propulsion Laboratory Science Team Simone D'Amico, Stanford University John Debes, Space Telescope Science Institute Shawn Domagal-Goldman, NASA Goddard Space Flight Center Sergi Hildebrandt, NASA Jet Propulsion Laboratory Renyu Hu, NASA
    [Show full text]
  • Unraveling the Mystery of Exozodiacal Dust
    Exploring the Formation and Evolution of Planetary Systems Proceedings IAU Symposium No. 299, 2013 c International Astronomical Union 2013 M. Booth, B. C. Matthews & J. R. Graham, eds. doi:10.1017/S1743921313008843 Unraveling the Mystery of Exozodiacal Dust S. Ertel1, J.-C. Augereau1,P.Th´ebault2,O.Absil3,A.Bonsor1, D. Defr`ere4,Q.Kral2, J.-B. Le Bouquin1, J. Lebreton1, V. Coud´e du Foresto2,5 1 IPAG, UJF Grenoble; 2 LESIA, Observatoire de Paris; 3 Universit´edeLi`ege; 4 Steward Observatory; 5 Bern University Abstract. Exozodiacal dust clouds are thought to be the extrasolar analogs of the Solar Sys- tem’s zodiacal dust. Studying these systems provides insights in the architecture of the innermost regions of planetary systems, including the Habitable Zone. Furthermore, the mere presence of the dust may result in major obstacles for direct imaging of earth-like planets. Our EXOZODI project aims to detect and study exozodiacal dust and to explain its origin. We are carrying out the first large, near-infrared interferometric survey in the northern (CHARA/FLUOR) and southern (VLTI /PIONIER) hemispheres. Preliminary results suggest a detection rate of up to 30% around A to K type stars and interesting trends with spectral type and age. We focus here on presenting the observational work carried out by our team. Keywords. infrared: stars, circumstellar matter, surveys, techniques: interferometric, techniques: high angular resolution 1. How to detect an exozodi The thermal emission from hot exozodiacal dust (typically several hundreds of kelvin up to the sublimation temperature, e.g., Lebreton et al. 2007) results in a near-infrared excess above the stellar flux (typically 1% for known systems).
    [Show full text]
  • Inner Solar System Is Filled with Dust Near the Ecliptic Plane
    + Olivier Absil ISSI team: Exozodiacal dust diks and Darwin Emmanuel Di Folco Hervé Beust Rémy Reche Alexander Krivov Philippe Thébault Torsten Loehne Vincent Coudé du Foresto Bertrand Menesson Pierre Kervella Observations of exozodiacal disks Jean-Charles Augereau LAOG, Grenoble, France Cambridge, August 2009 + Zodiacal dust in the Solar System Within ~2 AU, the inner solar system is filled with dust near the ecliptic plane Origin: tails of comets or when asteroids collide. It’s not a smooth cloud: Dust bands: asteroids families? Dust trails: short period comets? Resonant ring caused by the Earth + Zodiacal dust in the Solar System Tiny total mass : -8 equivalent to a medium-sized asteroid (~ 10 MEarth) But in the form of small grains, it is the most luminous circumsolar component, although it has a low vertical optical thickness (~ 10-7 @ 1AU) Potential noise source for future Earth-like finding missions Motivated several studies to search for exozodiacal, debris disks around nearby stars + Exozodis: observations Small angular separation + High contrast (>1:100) (near)-IR interferometry Direct measurement of disk to star contrast, with a precision of a few 0.1% Rough constraints on the spatial location CHARA interferometer, Mont Wilson + Exozodis: detection principle Non-destructive near-IR interferometry: An exozodiacal disk induces a loss of visibility This deficit is best detected at short baselines Fully resolved for baselines B ~10-30m B~200m Baseline, in meters + Fomalhaut A rich planetary system : HST: a Kuiper Belt, a planet VLTI/VINCI: Exozodiacal dust, that represents 0.88±0.12% of the stellar flux at λ= 2.2µm Absil et al.
    [Show full text]
  • Show Me the Planets! NASA's Exoplanet Exploration Program
    Show Me the Planets! NASA’s Exoplanet Exploration Program Dr. Gary Blackwood, Program Manager Dr. Karl Stapelfeldt, Program Chief Engineer Jet Propulsion Laboratory California Institute of Technology April 27, 2017 Caltech Board of Trustees Meeting Pasadena, California © 2017 All rights reserved © 2017 California Institute of Technology. Government sponsorship acknowledged. Artist concept of Kepler-16b Science Updates Discover & Characterize Program Overview: Implementing Astro2010 Priorities Plan Forward: Astro2020 Show Me the Planets! Seven ExoPlanets Above the Fold 2 Trappist-1 Discovery The Richest Set of Earth-sized Planets Ever Found Credit: NASA/JPL 3 A Familiar Habitable Zone Credit: Luc Forsyth 4 Trappist-1: a Relatively Small Star 5 How Spitzer Observed the Trappist-1 System Credit: NASA/JPL 6 Key Takeaways from Trappist Discovery • This is the richest set of Earth-sized exoplanets ever found orbiting a single star, with 3 in the habitable zone. • It shows that red dwarf stars, the most common type of star, can host rich planetary systems. More discoveries like this can be expected • The Trappist exoplanets will be top targets for future observations with the James Webb Space Telescope. The presence and composition of an atmosphere can be measured through infrared spectra taken during transit; but the observations will be difficult. • Most exoplanets do not transit their star. For the general case, direct imaging remains essential for measuring atmospheres and possible biosignatures. 7 LHS 1140: Super Earth, Super Girth A Super Earth in HZ of Red Dwarf at 39 ly • 1.4 Earth radius & 7 earth masses. Surface gravity is > 3x that of the Earth • Bright enough for JWST follow-up, but small scale height will make transit spectroscopy difficult Credit: Dittman et al.
    [Show full text]
  • A Search for Exozodiacal Dust and Faint Companions Near Sirius
    A Search for Exozodiacal Dust and Faint Companions Near Sirius, Procyon, and Altair with the NICMOS Coronagraph1 Marc J. Kuchner Palomar Observatory, California Institute of Technology, Pasadena, CA 91125 Michael E. Brown2 Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 ABSTRACT We observed Sirius, Altair, and Procyon with the NICMOS Coronagraph on the Hubble Space Telescope to look for scattered light from exo-zodiacal dust and faint companions within 10 AU from these stars. We did not achieve enough dynamic range to surpass the upper limits set by IRAS on the amount of exo-zodiacal dust in these systems, but we did set strong upper limits on the presence of nearby late-type and sub-stellar companions. Subject headings: binaries: visual — circumstellar matter — interplanetary medium — stars: individual (Altair, Procyon, Sirius) — stars: low mass, brown dwarfs arXiv:astro-ph/0002043v1 2 Feb 2000 1. Introduction Several main sequence stars are close enough that a large telescope operating at the diffraction limit can resolve the terrestrial planet-forming region within 10 AU from the star (Kuchner, Brown & Koresko 1998). We used the NICMOS coronagraph to image three of the nearest main-sequence stars in the near-infrared to look for circumstellar material—exozodiacal dust and faint companions—in this relatively uncharted circumstellar region. 1Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc. under NASA contract No. NAS5-26555. 2Alfred P. Sloan Research Fellow –2– Any dust orbiting close to one of our targets must have been generated recently by some population of larger bodies, since dust near a star quickly spirals into the star due to Poynting-Robertson drag (Robertson 1937).
    [Show full text]
  • Arxiv:1703.02540V2 [Astro-Ph.EP] 14 Feb 2018 KEYWORDS Exozodis – Exozodiacal Cloud – Debris Disc – Circumstellar Matter – Planetary Systems
    Exozodiacal clouds: Hot and warm dust around main sequence stars Quentin Krala,Alexander V. Krivovb, Denis Defr`erec, Rik van Lieshouta, Amy Bonsora, Jean-Charles Augereaud,e, Philippe Th´ebaultf, Steve Ertelg, J´er´emy Lebretond,e, and Olivier Absilc a Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK; b Astrophysikalisches Institut und Universit¨atssternwarte, Friedrich-Schiller-Universit¨at Jena, Schillerg¨aßchen 2-3, D-07745 Jena, Germany; c Space sciences, Technologies, and Astrophysics Research (STAR) Institute, Universit´ede Li`ege, 19c all´eedu Six Ao^ut,B-4000 Li`ege,Belgium; d Institut de Planetologie et dAstrophysique de Grenoble (IPAG, UMR 5274), Univ. Grenoble Alpes, F-38000 Grenoble, France; e CNRS, Institut de Planetologie et dAstrophysique de Grenoble (IPAG, UMR 5274), F-38000 Grenoble, France; f LESIA-Observatoire de Paris, UPMC Univ. Paris 06, Univ. Paris-Diderot, 92195 Meudon, France; g Steward Observatory, Department of Astronomy, University of Arizona, 933 N. Cherry Ave, Tucson, AZ 85721, USA ARTICLE HISTORY Compiled February 15, 2018 ABSTRACT A warm/hot dust component (at temperature > 300K) has been detected around ∼20% of A, F, G, K stars. This component is called \exozodiacal dust" as it presents similarities with the zodiacal dust detected in our Solar System, even though its physical properties and spatial distribution can be significantly different. Under- standing the origin and evolution of this dust is of crucial importance, not only because its presence could hamper future detections of Earth-like planets in their habitable zones, but also because it can provide invaluable information about the inner regions of planetary systems.
    [Show full text]
  • Abstract. the Keck Interferometer Is Being Developed by JPL and CARA As One of the Ground-Based Components of NASA’S Origins Program
    The Keck Interferometer: Instrument Overview and Proposed Science A..J.Booth, M.M.Colavita, TvI.Shao, P.N.Swanson, G.T.van Belle, S.L.Crawford, D.L.Palmer, L..J.Reder, ESerabyn, M.R.Swain, G.Vashist and .J.K.Wallace Jet Propulsion Laboratorp, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA 91 109 P.Wizinowich, R.Kendrick, W.Lupton, and J.Walker W. 1M. Keck Observatory, California Association for Research in Astronomy, 65-1120 Mamalahoa Hwy., Karnuela, HI 96743 Abstract. The Keck Interferometer is being developed by JPL and CARA as one of the ground-based components of NASA’s Origins Program. The interferometer will combine the two 10-m Keck telescopes with four pro- posed 1.8-m outrigger telescopes located at the periphery of the Keck site on Mama Kea. Incorporation of adaptive optics on the Keck tele- scopes with cophasing using an isoplanatic reference provides high sen- sitivity. Back-end instrumentation will include two-way combiners for cophasing and single-baseline measurements, a nulling combinerfor high- dynamic-range measurements, and a multi-way imaging combiner. Sci- ence objectives include the characterization of zodiacal dust around other stars, detection of hot Jupiters and brown dwarfs through multi-color differential-phase measurements, astronletric searches for planets down to Granus-mass, and a wide range of infrared imaging. 1. Introduction The Keck Interferometer will combine the two 10-m Keck telescopes with four proposed 1.8-m outrigger telescopes as an interferometric array capable of ad- dressing a broadrange of astronomical science. It is funded byNASA its a joint development between the Jet Propulsion Laboratory, California Institute of Technology (JPL) and the W.
    [Show full text]
  • The Exo-S Probe Class Starshade Mission
    The Exo-S probe class starshade mission The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Citation Seager, Sara et al. “The Exo-S Probe Class Starshade Mission.” Ed. Stuart Shaklan. N.p., 2015. 96050W. © 2015 Society of Photo-Optical Instrumentation Engineers (SPIE) As Published http://dx.doi.org/10.1117/12.2190378 Publisher SPIE Version Final published version Citable link http://hdl.handle.net/1721.1/106349 Terms of Use Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. Invited Paper The Exo-S Probe Class Starshade Mission Sara Seager*a, Margaret Turnbullb, William Sparksc, Mark Thomsond, Stuart B Shakland, Aki Robergee, Marc Kuchnere, N. Jeremy Kasdinf, Shawn Domagal-Goldmane, Webster Cashg, Keith Warfieldd, Doug Lismand, Dan Scharfd, David Webbd, Rachel Trabertd, Stefan Martind, Eric Cadyd, Cate Heneghand aMassachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, USA 02139- 4307; bGlobal Science Institute, P.O. Box 252, Antigo, WI, USA 54409; cSpace Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD, USA 21218-2410; dJet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA, USA 91109-8001; eGoddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD, USA 20771-2400; fPrinceton University, Department of Mechanical and Aerospace Engineering, Engineering Quadrangle, Olden Street, Princeton, NJ, USA 08544; gUniversity of Colorado, Center for Astrophysics and Space Astronomy, 389 UCB, Boulder, CO, USA 80309-0389 ABSTRACT Exo-S is a direct imaging space-based mission to discover and characterize exoplanets.
    [Show full text]
  • You Had Me at Habitable: NASA's Search for Habitable Planets And
    You Had Me at Habitable: NASA’s Search for Habitable Planets and Life Beyond the Solar System Dr. Gary Blackwood, Program Manager NASA Exoplanet Exploration Program Jet Propulsion Laboratory California Institute of Technology March 21, 2017 SETI Institute Weekly Colloquium Mountain View, CA © 2017 All rights reserved Artist concept of Kepler-16b Program Overview Science Updates How Do We Discover & Characterize Exoplanets? Progress towards 2010 Decadal Survey Priorities Plan Forward: Science and Technology You Had Me at Habitable Program Overview Science Updates How Do We Discover & Characterize Exoplanets? Progress towards 2010 Decadal Survey Priorities Plan Forward: Science and Technology You Had Me at Habitable NASA Exoplanet Exploration Program Astrophysics Division, NASA Science Mission Directorate NASA’s search for habitable planets and life beyond our solar system Program purpose described in 2014 NASA Science Plan 1. Discover planets around other stars 2. Characterize their properties 3. Identify candidates that could harbor life ExEP serves the science community and NASA by implementing NASA’s space science vision for exoplanets https://exoplanets.nasa.gov 3 SETI Mission Statement …and to apply the knowledge gained to inspire and guide present and future generations. 4 NASA Exoplanet Exploration Program Space Missions and Mission Studies Public Communications Kepler, WFIRST Decadal Studies K2 Starshade Coronagraph Supporting Research & Technology Key Sustaining Research NASA Exoplanet Science Institute Technology Development Coronagraph Masks Large Binocular Keck Single Aperture Telescope Interferometer Imaging and RV High-Contrast Deployable Archives, Tools, Sagan Fellowships, Imaging Starshades Professional Engagement NN-EXPLORE https://exoplanets.nasa.gov 5 ExEP is a Program Office within the NASA Astrophysics Division 6 ExEP Resides within NASA JPL Directorate Astrophysics Division, Science Mission Directorate Program Office (JPL) PM – Dr.
    [Show full text]